Fluid flow control valves

ABSTRACT

This disclosure relates to valves and valving systems for controlling the flow of fluids, particularly vapors and gases, through ports of relatively large area with relatively low pressure drops. The type of valve disclosed I call a &#39;&#39;&#39;&#39;curtain valve&#39;&#39;&#39;&#39;; it is comprised of an impervious flexible sheet (the curtain) movably installed to cover and uncover an opening or port on the upstream side so that the curtain seals around the edges of the port under the pressure differential across the port. To prevent deflection of the central part of the flexible sheet through the port opening a grid coextensive in area with the port opening may be provided on the downstream side, the bars of the grid being sufficient in number and spacing to support the flexible sheet or curtain which covers (or throttles) the port area. The particular type of curtain valve illustrated and described in this disclosure is characterized by an impervious sheet between reels at opposite ends of the grid, the sheet sliding across the grid as the reels are rotated together.

ilnited States Patent [191 Barnebey Aug. 13, 1974 FLUID FLOW CONTROL VALVES [75} Inventor: Herbert L. Barnebey, Columbus, ABSTRACT This disclosure relates to valves and valving systems [73] Assignee: Barnebey-Cheney Co., Colu b for controlling the flow of fluids, particularly vapors Ohio and gases, through ports of relatively large area with relatively low pressure drops. The type of valve dis- Flledi P 16, 1973 closed I call a curtain valve; it is comprised of an [21] APPL N04 351,290 impervious flexible sheet (the curtain) movably installed to cover and uncover an opening or port on the Related Appllcamn Data upstream side so that the curtain seals around the [63] Continuation of Ser. No. 218,! 14, Jan. I7, 1972, Pat. edges of the port under the pressure differential across No. 3,7 3,077. the port. To prevent deflection of the central part of the flexible sheet through the port opening a grid oo- [52] [1.8. CI. 2 extensive in area with the port pening may be pro- [51] Int. Cl. Flfik 13/00 vided on the downstream side, the bars of the grid [58] Field of Search 251 lDlG. 2; l37/599.l, b i uffici nt in number and spacing to support the 137/625-23 flexible sheet or curtain which covers (or throttles) the port area. The particular type of curtain valve il- References Cited lustrated and described in this disclosure is character- UNITED STATES PATENTS ized by an impervious sheet between reels at opposite 2,349,368 5/1944 Myers 26l/DIG. 2 ends Ofthe grldr the Sheet Shhhg across the ghd as the v Primary ExaminerArnold Rosenthal Attorney, Agent, or Firm-Wm. Henry Venable reels are rotated together.

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FLUID FLOW CONTROL VALVES CROSS-REFERENCE TO A RELATED PATENT APPLICATION This application is a continuation of my pending application Ser. No. 218,114 filed on Jan. 17, 1972 of the same title, now US. Pat. No. 3,773,077, limited to the sliding curtain valve illustrated in FIGS. 15, 16, 17, 19 and thereof which are identical with FIGS.-l 6, respectively, of this application.

SUMMARY OF THE INVENTION My invention relates to valves and valving systems for controlling relatively low pressure, large volume fluid flow. In the embodiments particularly illustrated and described below, the fluids are vapors or gases but the type of valving disclosed can be adapted to control liquid flows also and the term fluid as used herein has its usual meaning, referring to vapors, gases and liquids. The valve of this invention has the advantage of requiring relatively small space for installation, and simplicity in operation for valving either single or multiple ports, as compared, for example, to gate valves typical of the prior art. I call it a curtain valve; in brief, it is comprised of a flexible impervious sheet (the ,curtain) movably installed to cover and uncover, or to throttle, a single port or various members of an array of ports, upstream of the port in the direction of fluid flow, so as to seal around the edges of the ports under the pressure differential between the upstream and downstream sides thereof. To prevent deflection of the central portion of the impervious sheet through the ports, a grid coextensive in area with the port maybe provided in the downstream side of the impervious sheet, the bars of the grid being sufficient in number and spacing to support the flexible sheet or curtain which covers or throttles the port area. When thus supported by a grid, the impervious flexible sheet or curtain may be made of relatively thin and light material, although the port which it covers has a very large area. The particular type of curtain valve illustrated and described in this disclosure is characterized by having the impervious sheet between reels at opposite ends of the grid, the sheet sliding across the grid as the reels are rotated together to wind up on one reel while unwinding on the other reel. Two embodiments of this construction are given as examples. In one, the sheet has an area suffrcient to cover oneport on an array of several ports, the sheet being attached to continuous tapes extending to, and wound or unwound upon, the reels at opposite ends of the grid, such that the ports may be selectively covered, one by one, as the reels are wound or unwound. In the other embodiment, the sheet is in two sections each attached to one of the reels, thetwo sections being connected together between the reels by tapes for a distance approximating the length of one port of the array, such that the several ports may be selectively uncovered, one by one, as the reels are wound or unwound.

BRIEF DESCRIPTION OF DRAWINGS The annexed drawings illustrate a variety of embodiments of my invention, in a four duct, 1'2-port valve array chamber suitable for controlling the flow of gases and steam for a typical adsorption system having three adsorbers.

FIG. 1 is an isometric view of the valve housing from the outside. 1

FIGS. 2 and 3 are longitudinal sections through the chamber of FIG. 1 and FIG. 4 is a typical transverse section through this housing.

FIG. 5 is a view of the curtain-and-reel construction in one of the four duets with the reels unrolled sufficiently to show the curtain area.

FIG. 6 is a diagram of the curtain-and-reel device of FIG. 5 with the curtain in four different positions.

DETAILED DESCRIPTION Referring to the drawings which illustrate an embodiment of my invention in a l2-port array, the valve assembly is comprised of a housing 10d having chambers on the downstream side of which are twelve outlet ports 41 through 52 inclusive. A series of grid bars 13 flush with the upstream side of each outlet port is provided. The grid bars shown in FIG. 4, extend from end to end of said opening but they may extend from side to side or, if preferred, such bars 13 may extend both lengthwise and transversely across said opening in the form of a grating. A flexible sheet (53 and 54) of area somewhat greater than that of the outlet ports to be selectively closed is movably supported within the housing 10d adjacent the upstream side of the grid bars 13, as subsequently described herein.

When the ports are covered, or partially covered, by the sheets 53 or 54, the fluid pressure in the upstream side presses the impervious flexible sheet against the sides of the port openings and the grid bars 13. The sheet being thin and flexible, such pressure substantially seals the opening against fluid flow when closed.

This l2-port valve array is particularly adapted to control the flow of gas and vapors in a three-adsorber installation.

Such systems are well known to those skilled in the art, and the following description is mainly concerned with the valving for the desired flow sequence. In this example, the three adsorbers are provided to remove residual components, such as a solvent vapor, from a gas such as air. Three adsorbers are each packed with a suitable adsorbent, such as granular activated carbon, through which the solvent laden air is passed until the adsorbent is saturated with the adsorbed vapor. Then low pressure steam is passed through each adsorber to remove the solvent and regenerate the adsorbent for a successive gas treatment. The regeneration of the adsorbers is performed in the respective adsorbers in sequence at spaced time intervals, the time for regeneration being much shorter than the time for adsorption.

There are thus required four inlet and outlet ducts, two for the air flow and two for the flow of low pressure steam. In the pair for air flow the inlet duct is item 37 and the outlet duct is item 38 on the drawings; in the pair for low pressure steam the inlet duct is item 39 and the outlet duct is item 40. Air from the inlet duct 37 is channeled into the bottoms of adsorbers by valves 41, 42 and 43 respectively, and after passing through the adsorbers the air discharged at the top is channeled to outlet duct 38 by valves 44, 45 and 46 respectively. Similarly, steam to regenerate the adsorbers is channeled from the steam inlet duct 39 into the bottoms of the adsorbers by valves 47,48 and 49, respectively, and

discharged from the tops of the adsorbers to outlet duct 40 through valves 50, 51 and 52.

The array of valves and ducts embodying my invention is assembled in a unitary valve housing d shown in FIG. 1. The ends of the conduits to the bottoms of the adsorbers are marked with the letters U, V, and W, respectively, in the figures, and the ends of the conduits from the tops of the adsorbers are marked X, Y and Z.

The interior construction of the twelve valve array housing (seen externally in FIG. 1) is shown in FIGS. 2, 3, and 4, in which FIG. 2 is a longitudinal section through the air ducts 37 and 38, FIG. 3 is a longitudinal section through the steam ducts 39 and 40, and FIG. 4 is a typical transverse section through all four ducts at approximately the center of a set of four valve ports, the housing having three such sets to provide the twelve valve ports described above. As shown in FIG. 2, the three air inlet valve openings are opened and closed selectively by a single movable curtain 53 which are embodiments of the invention hereinafter claimed. The three air outlet valves are opened and closed by three separate curtains 140, which may be of the type disclosed in Myers US. Pat. No. 2,349,368, FIGS. 1 and 2. Each of these openings is provided with curtainsupporting grid bars 13 and the curtains are movably mounted on the up-stream sides of the openings.

Similarly, the three steam inlet valves shown in FIG. 3 are opened and closed by a single movable curtain v 54, which are also embodiments of the invention hereinafter claimed, and the three steam outlet valves are separate curtain valves 14a of the type disclosed in the Myers patent above referred to.

The curtain 53 is a flexible sheet of width wider than the port openings and a length slightly longer than the length of the openings, attached to continuous tapes 18a wound on reels 20b adjacent opposite ends of the duct 37. By rotating these reels, the curtain 53 may be placed to cover any one of the three port openings or to uncover all three, as indicated more particularly in FIG. 6. The curtain 54 is a flexible sheet attached at each end to reels 200 located adjacent the ends of steam inlet duct 39 this sheet being discontinuous for a length approximating the length of a single port opening, and being connected across this length by spaced tapes 18b. By rotating the reels 200 all three ports may be covered by the flexible sheet 54, or any one may be selectively uncovered by placing the discontinuity in the sheet (bridged by the tapes 18b) adjacent any desired port opening. Thus the curtains in air inlet duct 37 and in steam inlet duct 39 exemplify a reversal of parts of the same construction; in one, the curtain is one-port in length whereas in the other the opening through the curtain is one-port in length. This construction may be characterized as the sliding-curtain type. As used herein, the term connected to said reels as applied to connection of the flexible sheet for covering the port opening, comprehends either mediate (as by tapes) or immediate (as direct) connection.

The selection of separate curtain valves 14a for each of the six port openings conducting the outlet of air and steam to ducts 37 and 39, instead of the single movable curtain type described above, is because the ducts 37 and 39 are on the downstream sides of the port openings whereas the curtain type valve must be on the upstream sides of the ports and grid bars. Inthe valve array as seen in FIGS. 2 and 3, each of thesesix outlet ports face isolated compartments of the housing on the upstream side and a continuous curtain would have to pass through the walls of these compartments, requiring slots through the top and bottom walls. This is possible, and some sort of seals can of course be provided at the slots to minimize leakage therethrough, but I prefer to use separate curtains entirely contained within the compartment and avoid slots between compartments.

The operation of the reels to move the curtains in the housing 10d, for the desired fluid flow through the adsorbers in a predetermined sequence, would follow a timing dependent, of course, on the amount of adsorbent in each adsorber, the rate of air and steam flow therethrough, and the amount of the component in the air stream to be adsorbed. The regeneration time usually varies from one-sixth to one-fourth of the adsorption time, a range generally typical of commercial practice. The cycles for the three adsorbers are staggered in a phased relation such that the adsorbers are regenerated separately one after the other, at approximately equally spaced time intervals, all three adsorbers being on stream approximately half the time, and two adsorbers being on stream approximately the other half of the time. The control instrumentation for operating the motors driving the valve curtain reels according to such a program is not shown or described in this disclosure, such instrumentation being well known to control engineers, but it is evident from the foregoing description of the l2-valve array that the construction lends itself to automatic, programmed control in predetermined sequence.

The material selected for the impervious flexible sheet curtains herein disclosed may be any material suitable for the particular intended application. For the l2-port array controlling three adsorbers, a tough plastic made to withstand temperatures such as that of low pressure steam, such as sold under the trademark MYLAR," may be used. For relatively high temperatures, as a valve of the type applied to handle furnace gases, the curtain may be stainless steel. Where the fluid temperature is relatively low, an impregnated cloth curtain such as rubberized duck may be used. The curtain material is not, of course, limited to the above three examples.

I claim:

1. A valve for controlling the flow of fluids through selected ports in series array, comprising a gridwork flush on one side with the upstream face of said series of ports, an impervious flexible sheet having a width greater than the width of the ports in said series and a length greater than a single port of said series, so as to cover said single port when placed opposite thereto against said gridwork on the side flush with the upstream face thereof, a pair of reels one of which is rotatably mounted adjacent one end of said series and the other of which is rotatably mounted adjacent the opposite end of said series on the upstream face side, said curtain being connected to said reels on opposite sides, and means for rotating said reels whereby said curtain is caused to slide over said gridwork on the upstream face of said series of ports.

2. A valve as set forth in claim 1 in which the length of said curtain is substantially the same as the length of one port opening only in said series and the connection of said curtain to said reels is by tapes attached to said curtains and said reels.

3. A valve as set forth in claim 1 in which said impervious flexible sheet is discontinuous for a length approximating the length of a single port opening, the opposite ends of said sheet are directly connected to said reels, and a set of tapes connecting said discontinuous sheet across said length. 

1. A valve for controlling the flow of fluids through selected ports in series array, comprising a gridwork flush on one side with the upstream face of said series of ports, an impervious flexible sheet having a width greater than the width of the ports in said series and a length greater than a single port of said series, so as to cover said single port when placed opposite thereto against said gridwork on the side flush with the upstream face thereof, a pair of reels one of which is rotatably mounted adjacent one end of said series and the other of which is rotatably mounted adjacent the opposite end of said series on the upstream face side, said curtain being connected to said reels on opposite sides, and means for rotating said reels whereby said curtain is caused to slide over said gridwork on the upstream face of said series of ports.
 2. A valve as set forth in claim 1 in which the length of said curtain is substantially the same as the length of one port opening only in said series and the connection of said curtain to said reels is by tapes attached to said curtains and said reels.
 3. A valve as set forth in claim 1 in which said impervious flexible sheet is discontinuous for a length approximating the length of a single port opening, the opposite ends of said sheet are directly connected to said reels, and a set of tapes connecting said discontinuous sheet across said length. 